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elliptic-shiho/OCR.txt

Created April 30, 2018 21:57
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ASIS CTF 2018 Quals: Uncle Sam Solver
Raw
OCR.txt
factoreal @ myThinkMate in ... E$ python Uncle_Sam.py ]
def generate_key(k): p, q = getPrime(k), getPrime(k) pubkey = p**2 * q 1 = (p-1)*(q-1) / gcd(p-1, q-1) privkey = inverse(n, 1) return pubkey, privkey
def encrypt(m, pubkey): return pow(bytes_to_long(m), pubkey, pubkey)
pubkey = 104324738132004141014637484768390560888606798880281575965549007150696481142773349666805536470082277990816674819353434190328538733265808156204153422896153845183002504176253763998515034491758406482 761535653576387253992598998411706820755549870058537633073142835948979160031963607977702534421724847548583529868943792600395857814178437985795126497310921480391644570296404789944700219154896523988409580209 179878798874541517857859720681512291543835163667268135551798241012356996124256319448039934796175367815921021799352673830679650366056316302928741973221024757979326689108517881704753675846523995086126659252 420639086982297246913756604517669027781335256339283884741767452925162741947981509786889099315321551548887709776027239948311101360261855484609689380510882721134446779707235207243059131848509167701126191299 2157762106672216780766138057271434398274272110062768324672899209610001835423246735718435995420720133657793744810610657
privkey = 10571787767222429578429167538554675012960147216337952737536712823800347179309734176339199950391365954208752080836428716764534955589777442817628882903147770359477634126816043366897623719833012490 437254689795395524177847532207416046976716256623435890774041280521124759869848164020795682719904841994984861973105086075780808210684495360217650324778653542342310423956691071352869129869233214978368903272 277200997440471678331220088555534387761109499811730797039924164021355382004346014049380340419077417191296265107510098383407125902103832288611466002878822909487254551605475770006826462802452439499579513546 4746570071201
enc = 343369686707916921497078851452395954252074753628024855326592148594828266567853497784448902839960599855457261387659174943864861324798607407210198762531665500523668627672623380100283047707927966101715 266190355476680204081288124100983003649559499979731342450364456322062273208742008750774795951290651360492364136674198126979777860541228166734597108964573061640243513571440689299166495541329990802602494896 619995591485311779060353650700199981044058309406067935205196708178000370643018639282003328307492888263256672104905274453644042024751439967243049147724769464785043328741645419214885736940487139062463786022 104540986811119563549305718088453842093257734689508882969016290658885961965896726616361694426487326338043950416067501288065942862535560013037283761552797410980713186506671844418096395304234050342551849999 867017770968633512178545044838766793795733222455421862835695299142219006201321417882617773291364153890050471244104
factoreal @ myThinkMate in .... $ 1
Raw
solve.py
from scryptos import *
pubkey = 1043247381320041410146374847683905608886067988802815759655490071506964811427733496668055364700822779908166748193534341903285387332658081562041534228961538451830025041762537639985150344917584064827615356535763872539925989984117068207555498700585376330731428359489791600319636079777025344217248475485835298689437926003958578141784379857951264973109214803916445702964047899447002191548965239884095802091798787988745415178578597206815122915438351636672681355517982410123569961242563194480399347961753678159210217993526738306796503660563163029287419732210247579793266891085178817047536758465239950861266592524206390869822972469137566045176690277813352563392838847417674529251627419479815097868890993153215515488877097760272399483111013602618554846096893805108827211344467797072352072430591318485091677011261912992157762106672216780766138057271434398274272110062768324672899209610001835423246735718435995420720133657793744810610657
privkey = 105717877672224295784291675385546750129601472163379527375367128238003471793097341763391999503913659542087520808364287167645349555897774428176288829031477703594776341268160433668976237198330124904372546897953955241778475322074160469767162566234358907740412805211247598698481640207956827199048419949848619731050860757808082106844953602176503247786535423423104239566910713528691298692332149783689032722772009974404716783312200885555343877611094998117307970399241640213553820043460140493803404190774171912962651075100983834071259021038322886114660028788229094872545516054757700068264628024524394995795135464746570071201
enc = 343369686707916921497078851452395954252074753628024855326592148594828266567853497784448902839960599855457261387659174943864861324798607407210198762531665500523668627672623380100283047707927966101715266190355476680204081288124100983003649559499979731342450364456322062273208742008750774795951290651360492364136674198126979777860541228166734597108964573061640243513571440689299166495541329990802602494896619995591485311779060353650700199981044058309406067935205196708178000370643018639282003328307492888263256672104905274453644042024751439967243049147724769464785043328741645419214885736940487139062463786022104540986811119563549305718088453842093257734689508882969016290658885961965896726616361694426487326338043950416067501288065942862535560013037283761552797410980713186506671844418096395304234050342551849999867017770968633512178545044838766793795733222455421862835695299142219006201321417882617773291364153890050471244104
n = pubkey
d = privkey
pow2 = pow(2, n*d, n)
assert pow2 != 2
g = gcd(pow2 - 2, n)
assert g != 1 and g != n
assert n % g == 0
pq = g
print [long_to_bytes(pow(enc, d, pq))] # => ['ASIS{Y0u_c4N_m4n493_Schmidt_5am0A_CryP7o_SysT3M!!}']
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